WASHINGTON -LRB- CNN -RRB- -- States appear to be taking more action to keep guns out of the hands of people with mental health problems in the wake of the Virginia Tech shootings , new figures show .

Mental health problems would prohibit potential buyers from purchasing a gun .

Submissions of mentally ill patients ' records to the FBI 's National Instant Criminal Background Check System for gun buyers have more than doubled since the massacre in April , the Justice Department announced Thursday .

Currently , states are not required to send reports of mental health problems , which would prohibit buyers from purchasing a gun .

But after the shootings -- when a student with a history of mental health problems killed 32 people before taking his own life -- the number of submissions to the database grew from 174,863 during the first half of the year to 393,957 from July to November .

The number of states submitting the information also grew , from 23 before the Virginia Tech tragedy to 32 after it .

The majority of the new records came from California authorities , who submitted more than 200,000 entries , the Justice Department said . Ohio boosted the amount of entries from three in March of this year to 7,845 in November .

`` Instant background checks are essential to keeping guns out of the wrong hands , while still protecting the privacy of our citizens , '' Attorney General Michael Mukasey said to the National Association of Attorneys General .

`` But as we learned in the tragedy at Virginia Tech , the checks must be accurate and complete to be effective . ''

Virginia Tech shooter Seung-Hui Cho was judged a danger to himself and ordered to get outpatient mental health treatment in 2005 , but there was no indication he followed up .

Virginia did not report his name to the FBI system because he had n't been committed to a mental health facility .

Cho bought one of the guns he used in the massacre online from an out-of-state dealer , picking it up from a Blacksburg , Virginia , pawn shop after background checks were complete . He bought his other pistol from a Roanoke gun dealer a month before the shooting .

Officials say making sure information -- such as mental health records -- that would keep a person from buying a gun is available at a national level ensures that the individual does n't go across state lines to try to make a purchase .

Background checks , however , are n't necessary for firearms purchases made at gun shows or from a private seller , which , according to estimates , account for about half of the guns sold in the United States each year . E-mail to a friend

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Number of records given to the FBI more than doubles since Virginia Tech massacre

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The number of states submitting the information also grows

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Attorney General Mukasey : Checks must be accurate and complete to be effective

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The majority of the new records come from California